LONDON — Standard Chartered said on Tuesday that it had received accusations of potential wrongdoing by officials at an Indonesian power company in which it is an investor.

The London-based bank, whose business is largely in Asia, said that it had referred the accusations to “appropriate authorities,” without identifying them.

The United States Justice Department’s foreign bribery unit is the authority looking into the accusations, a person briefed on the matter said.

Under a so-called deferred-prosecution agreement with United States authorities, Standard Chartered is required to report any potential wrongdoing to the Justice Department. At the same time, such additional misconduct could prompt prosecutors to re-evaluate whether to revoke the deferred-prosecution agreement and force the bank to plead guilty.

The 2012 settlement between the bank and Washington followed an investigation into accusations that Standard Chartered had transferred billions of dollars for Iran and other countries that are affected by United States sanctions.

In its statement on Tuesday, Standard Chartered said that it had conducted its own review into potential wrongdoing at the power company, MAXpower Group.

The Wall Street Journal reported earlier on Tuesday that the investigation was related to accusations that MAXpower officials had paid bribes to win contracts.

The MAXpower inquiry is another potential blow to Standard Chartered’s reputation as William T. Winters, the lender’s American chief executive, seeks to turn around its prospects.

After the 2012 deferred-prosecution agreement with the United States, the bank also increased its spending on compliance and appointed a board-level financial crime risk committee to shepherd its compliance program.

In 2014, after prosecutors reopened their inquiries to examine whether Standard Chartered failed to disclose the extent of its wrongdoing to the government, the bank agreed to extend the period of the agreement until December 2017.

MAXpower, based in Jakarta, is a developer, owner and operator of small and medium-sized gas-fired power plants in Southeast Asia and is a distributor of General Electric Jenbacher power equipment.

Standard Chartered invested in the company in 2012, according to MAXpower’s website. The bank declined on Tuesday to confirm the size of its stake in the company.

MAXpower’s chairman and chief executive, Greg Karpinski, is a former managing director in Standard Chartered’s private equity business and the former co-head of the private equity business’s energy, resources and infrastructure team. He joined the company as chairman and C.E.O. last year, according to his LinkedIn page.

Three executives in Standard Chartered’s private equity business also serve as directors on MAXpower’s board.

Standard Chartered reported a profit of $394 million in the first half of 2016, down from $1.46 billion in the first six months of 2015. It posted a loss of $2.36 billion for the full 2015 year.

Ben Protess contributed reporting from New York.

A version of this article appears in print on , on Page B3 of the New York edition with the headline: London Bank’s U.S. Bargain Is Imperiled by New Claims. Order Reprints | Today’s Paper | Subscribe